A Baltimore man received twin life sentences Wednesday for sexually assaulting and murdering his children's mother at a house where she was staying in the city's Waltherson neighborhood.

Shawn Stevenson, 43, had been in a relationship with Somchanh Sipayboun for 13 years, but they had been fighting in the months before her death, according to prosecutors. Sipayboun moved out and took her children to live her sister in the 5400 block of Hilburn Avenue in a home that the couple owned.

On April 23 of last year, Stevenson told her the house was being sold and that she had to move out. Sipayboun called her sister to help move her things, but when the sister arrived she found Sipayboun naked and dead in the bathtub with the water still running.

Police said when they charged Stevenson with murder that at first they thought Sipayboun might have killed herself. But an autopsy report showed that her spine and collar bone were broken, and that she had been bound with duct tape, sexually assaulted, strangled and stabbed 14 times.

Police were also able to track the couple's cell phones and found they were both in the same area at the time of the killing.